In a first-of-its-kind study, researchers have proven that coronaviruses can be quickly and efficiently killed using ultraviolet light-emitting diodes (UV-LEDs).

The researchers found that the optimal wavelength for killing HCoV-OC43, a coronavirus strain used as a surrogate for SARS-CoV-2 because of their similarities, was 265 nanometers. However, a wavelength of 285 nanometers had a similar result, which matters because 285-nanometer bulbs are much less expensive than 265-nanometer bulbs.

“UV disinfection has been around for a while, but UV-LEDs are still very new, and so is their use,” lead study author Yoram Gerchman, PhD, a biochemist and professor at the University of Haifa and Oranim College in Isreal, tells Verywell. “Part of the problem is, the lower the wavelength, the more expensive and less efficient is the UV-LED, so there is much interest in the higher wavelength.”

Gerchman says that his paper is an “important step” in using UV-LED devices for disinfecting purposes.

Ultraviolet light is a type of electromagnetic radiation. It’s mostly invisible to the human eye and travels in a wavelength pattern at the speed of light.2

The most common form of UV radiation is sunlight, which produces UVA, UVB, and UVC rays.2 UVA rays have the longest wavelengths, followed by UVB, and finally UVC rays.

Lewis Nelson, MD, chair of the Department of Emergency Medicine at Rutgers New Jersey Medical School, tells Verywell that the findings are “not at all” surprising. Nelson did not work on the study. Other forms of UV light have already been used for disinfecting purposes, and there's no reason to think that UV-LED light would be any different.

How UV-LED Light Can Be Used

While UVC lights are used commercially in products like phone disinfecting devices, UVC light can cause severe burns of the skin and eye injuries.2 “They need to be properly positioned to avoid causing eye or skin damage, which is essentially sunburn,” Nelson says.

Many UVC disinfecting products work inside a case or box to prevent people from being harmed by the rays. However, that arrangement makes it tricky to use UVC on a larger scale for disinfecting homes.

Gerchman proposes using UV-LED lights in air conditioning systems to help filter air that might contain SARS-CoV-2, which "could help in reducing exposure."

The study's co-authors also proposed using the technology in vacuum and water systems to quickly and efficiently disinfect large surfaces and spaces. Gerchman says that “UV in general and UV-LEDs are effective in combatting pathogens,” but adds that “UV should be used carefully.”

“I believe we are nearing the end of the COVID-19 [pandemic] with the vaccination approval, but airborne and waterborne pathogens—especially antibiotic resistance pathogens—will be with us for many years to follow,” Gerchman says. “UV is and will take part in battling such.”

What This Means For You